The invention relates to a device for separating individual sheets combined into a stack, particularly, sheets of film used in X-ray equipment.
A known problem in existing film changers, particularly in connection with X-ray installations, is the separation of individual sheets of flat film stacked in a feeder magazine in such a manner that only one sheet is transported to the exposure station of the film changer. Delivery of a plurality of sheets simultaneously would make an exposure impossible.
A presently known type of film changer calls for the film sheets in the feeder magazine to be individually disposed between disks. In this type of film changer, the sheets of film must be perforated in the two front edge corners disposed in the direction of transport, so that the sheets can be seized by pins of two conveyor belts guided along the feeder magazine for transport into the exposure station of the film changer. Accordingly, a significant disadvantage in this type of film changer is that only appropriately perforated film sheets can be used.
A further type of known film changer is disclosed in U.S. Pat. No. 3,616,736, which corresponds to German GLP 1,942,988. In this type of film changer, individual sheets of film are retained between disks, partially by means of spring pressure. A feed arm is provided with a claw means which respectively seizes the uppermost film sheet of the stack at its back edge for removing the sheet of film in the transport direction from the feeder magazine to the exposure station. The feeder magazine of this film changer must be manually loaded with sheets of film in a dark room. A further significant disadvantage of this type of feeder mechanism is that the transport path for film through the film changer must be disposed in a horizontal plane, which increases the overall space taken up by the film changer. Any sort of oblique positioning of the film changer with respect to the feeder magazine renders the transport of film sheets from the feeder magazine impossible.
The present invention concerns a novel construction for film sheet magazines which is both compact and in which the sheets of film are separated from one another in such a manner that a reliable and faultless delivery of consecutive single sheets of film from the magazine is guaranteed. The inventive magazine construction lends itself to either mechanical or automatic loading.